The CEL-2a from Peavey is a single-rack space, dual compressor that can be operated as either two independent compressors, or as a linked stereo compressor with true RMS summing. Soft-knee topology is used for the compressor and expander functions, which provide smooth transition curves. This results in dynamic changes being less obvious and more aesthetically pleasing, as well as being easier to adjust.
The downward expander section has threshold and ratio adjustments to allow it to be used for noise reduction (slight ratio) or a gate (high ratio). An LED lights when it is active. The compressor has attack and release controls in addition to threshold and ratio controls for complete versatility. Any level lost due to compression can be made up by the gain control.
The limiter is an infinite ratio compressor that keeps the output from exceeding a level set by its threshold control and has only one adjustment. It is totally independent of the compressor's settings and can be used to stop peaks from getting through when only mild compression (a low ratio setting in the compressor section) is desired. It has its own LED to indicate when it has been activated.
A side-chain insert (with its own enable switch) in the detector path allows manipulation or replacement of the detector signal. Built into the side-chain are two selectable filters - a low-cut filter and a "de-ess" filter. These functions can be used simultaneously.
The unit has fully-balanced inputs and outputs, with XLR and 1/4" jack connections. A special "one cable" in/out 1/4" TRS jack has is provided to allow the use of a standard 1/4" stereo cable to directly connect the unit to an insert jack of a mixer. High-quality, voltage-controlled amplifier (VCA) and RMS-rectifier integrated circuits are used to maintain low distortion and excellent noise performance.